An Etymological Dictionary of Astronomy and Astrophysics

The → SI unit of → electric current; symbol A. It is defined by taking the fixed numerical value of the → elementary charge, e, to be 1.602 176 634 × 10^-19 when expressed in the unit → coulomb (C), which is equal to A s, where the → second (s) is defined in terms of Δν_Cs.

See also: Named after the French physicist and mathematician André-Marie Ampère (1775-1836), one of the pioneers in studying electricity, who laid the foundation of electromagnetic theory.